Probably all the same my preferred crypto currency is bitcoin, this is the best choice for me. And not only for me, many more people are interested in bitcoin.
For me i still prefer bitcoin as the best of cryptocurrency next is ethereum. Both are obviously preferred coins today as they constantly holding an impressive performance. These two coins consistently stable inspite of some downfalls at times. I can say that an investment to these coins are worthy enough. But it is for you to find out so you can choose your own preferred coin.